Many modern search engines retrieve Web documents by literally matching terms in the Web documents with those in a search query using lexical matching methods. However, such lexical matching methods can be inaccurate due to language discrepancies between Web documents and search queries. For example, language discrepancies often occur because concepts are expressed using different vocabularies and language styles in Web documents versus search queries. Therefore, in many cases, the retrieval of appropriate Web documents relating to a particular search query may be difficult due to such language discrepancies.